Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdd3211cd2d3332c…

MALICIOUS

PDF

77.0 KB Created: 2021-08-31 18:30:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 17361f5263180205584a426ff2deb0a4 SHA-1: 625506b5a24f9268ca9c708dcb52d6f70d42e7bd SHA-256: fdd3211cd2d3332c535d6aab472a6ce37a20aace8a24ae2cf56938c8aa043068
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as a malicious PDF by multiple heuristics and a machine learning classifier. It contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, suggesting a link farm designed to redirect users. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://harchovyk.com/userfiles/file/44082361017.pdf In PDF document text
    • http://millecolori.it/images/file/vewugedegowamuz.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/1ce83684804c7824c166280405a82456/48365976750.pdfIn PDF document text
    • https://ascend.sut.ac.th/ce/2017/src/plugins/ckfinder/userfiles/files/37836388254.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608231778588b---tetezomepokajusa.pdfIn PDF document text
    • http://meyanko.com/userfiles/file///tugowedi.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/50298457783.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/22742759551.pdfIn PDF document text
    • http://hitechdentalhouston.com/uploads/files/19971633487.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-7-12/20210712213423940786.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6adebbd523---degemifejetefofeferototix.pdfIn PDF document text
    • http://francescasciortino.it/userfiles/files/durimekelaj.pdfIn PDF document text
    • https://deitratech.com/userfiles/file/89668982785.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16092b926e5fe4---kewuduti.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/wujekoxikufoxiwepoza.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093e4711e960---kowafizokaru.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608701c66e9fd---73064900853.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/voguzawulijazonoli.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/wutan.pdfIn PDF document text
    • https://digireg.pl/upload/sitanoxo.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/93d864034b42d668025996150f927e2a/53068068318.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/gorobir.pdfIn PDF document text
    • http://biplano.eu/userfiles/files/satosofe.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/a4ceffbbe8c8ef18ee2511f553ac1522/34849213793.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/zifinixo.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0f0ced63e---tudupiputomin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=engineering+business+plan+examples+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cadb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCADB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e2ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2ED 16536 bytes
SHA-256: 1620655acff26706c244f86c51717b83287dfdb806c719e2539ed4b05ecc9945
font_02_sfnt_off00010d8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D8E 10948 bytes
SHA-256: 8200f5d3c061d7a93f0f82ca59d2f3703f00d48d25c4b3dc6b9f86cad5007193